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trying various things
Thank you Andrew and Darin - you gave me some good ideas to think about and play with.
As you say Andrew, a BSFC map would be about impossible to come by for my 4 cyl camry. But it seems fair to guess that the BSFC ratio would be best with RPMs somewhere around 2K, and the throttle fairly wide.
And doing that immediately kicks the automatic into a lower gear. So the game I have been trying is a brisk acceleration, followed by light throttle to promote upshift. Depending on speed goal, this may then be followed by as much throttle as possible without causing downshift.
I have also tried a related strategy on a rolling highway. The car seems to cruise with good FE at around 60 mph. So going downhill, I try to gain some speed with light throttle, but try to keep the FE above a floor level of around 33. On the uphill, I try to continue to maintain the FE above the floor level, which means fairly constant throttle. But as speed drops this becomes impossible. At that point, I lighten the throttle to keep the fe above the floor, but speed tends to drop fast.
And here is the funny part:
I give it lot of throttle - as much as possible without causing a downshift. The theory is that I am putting gaining kinetic energy from a part of the BSFC map that is more efficient. I think this is workable because the camry has a reasonable cd of around .28.
Anyway, I have gotten just over 36 mpg on the highway with this strategy. But as it turns out, that is just what I get on my control run using more of the constant throttle method! Oh well. Still, the second method got me around the run at a higher overall speed...
The auto does make this experiments difficult. I wish there was a way to easily change the shift points. My 1985 Camry, which I will soon sell, had a switch to change the transmission shift strategy to economy. With that vehicle, and no eco driver's ed, I was averaging 34 mpg on drives that had a fair amount of highway. And I was doing it at speed! Ok, I did blueprint the engine a couple of years ago...
Harry
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